VB.Net/XML/XML DataSet

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Load xml document to DataSet

Imports System
Imports System.Xml
Imports System.Xml.Schema
Imports System.IO
Imports System.Drawing
Imports System.Drawing.Drawing2D
Imports System.Collections
Imports System.Data
Imports System.Windows.Forms

Public Class MainClass
    
    Shared Sub Main()
        Dim DSStudentClasses As New DataSet()
        Dim tmpNode As XmlNode
        " Load the schema into the DataSet
        DSStudentClasses.ReadXmlSchema("StudentClasses.xsd")
        " Load the DataSet into the data document
        Dim XDocStudents As New XmlDataDocument(DSStudentClasses)
        " Load the data into the data document
        XDocStudents.Load("Students.xml")
        Console.WriteLine("Students in DataSet:")
        Dim Row As DataRow
        For Each Row In DSStudentClasses.Tables("Student").Rows
            Console.WriteLine("{0}:{1}", Row("Name"), Row("GPA"))
            tmpNode = XDocStudents.GetElementFromRow(Row)
            Console.WriteLine( _
                  "   Locker Combination (from XML, not DataSet): {0}", _
                  tmpNode.SelectSingleNode("LockerCombination").InnerText)
            Dim Subject As DataRow
            For Each Subject In Row.GetChildRows("StudentClasses")
                Console.WriteLine("   {0}", Subject("Title"))
            Next
        Next
    End Sub
End Class
"student.xml
"<?xml version="1.0" encoding="utf-8" ?>
"<Students>
"  <Student ID="1">
"    <Name>Joe Wang</Name>
"    <Age>30</Age>
"    <GPA>2.95</GPA>
"    <LockerCombination>10-12-35</LockerCombination>
"    <Class Title="Biology" Room="100" />
"    <Class Title="English Lit" Room="101" />
"  </Student>
"</Students>
"student.xsd
"<?xml version="1.0" standalone="yes"?>
"<xs:schema id="Students" xmlns=""
"                        xmlns:xs="http://www.w3.org/2001/XMLSchema"                         xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
"  <xs:element name="Students" msdata:IsDataSet="true">
"    <xs:complexType>
"      <xs:choice maxOccurs="unbounded">
"        <xs:element name="Student">
"          <xs:complexType>
"            <xs:sequence>
"              <xs:element name="Name" type="xs:string"
"                          minOccurs="0" msdata:Ordinal="0" />
"              <xs:element name="GPA" type="xs:float"
"                          minOccurs="0" msdata:Ordinal="2" />
"              <xs:element name="Class"
"                          minOccurs="0" maxOccurs="unbounded">
"                <xs:complexType>
"                 <xs:attribute name="Title" type="xs:string" />
"                  <xs:attribute name="Room" type="xs:string" />
"                  <xs:attribute name="StudentID" type="xs:int"
"                                use="prohibited" />
"                </xs:complexType>
"              </xs:element>
"            </xs:sequence>
"            <xs:attribute name="ID" type="xs:int" />
"          </xs:complexType>
"        </xs:element>
"      </xs:choice>
"    </xs:complexType>
"    <xs:unique name="StudentID" msdata:PrimaryKey="true">
"      <xs:selector xpath=".//Student" />
"      <xs:field xpath="@ID" />
"    </xs:unique>
"    <xs:keyref name="StudentClasses" refer="StudentID"
"               msdata:IsNested="true">
"      <xs:selector xpath=".//Class" />
"      <xs:field xpath="@StudentID" />
"    </xs:keyref>
"  </xs:element>
"</xs:schema>


Read XML schema with DataSet and output its structure

Imports System
Imports System.Xml
Imports System.Xml.Schema
Imports System.IO
Imports System.Collections
Imports System.Data

Public Class MainClass
    
    Shared Sub Main()
        Dim MyDS As New DataSet()
        MyDS.ReadXmlSchema("book.xdr")
        Console.WriteLine("Book Structure:")
        Dim Table As DataTable
        For Each Table In MyDS.Tables
            Console.WriteLine("Table {0}", Table.TableName)
            Dim Column As DataColumn
            For Each Column In Table.Columns
                Console.WriteLine("  {0}", Column.ColumnName)
            Next
        Next
    End Sub
End Class
"book.xdr
"<?xml version = "1.0"?>
"<Schema xmlns = "urn:schemas-microsoft-com:xml-data">
"   <ElementType name = "title" content = "textOnly" 
"      model = "closed" />
"   <ElementType name = "book" content = "eltOnly" model = "closed">
"      <element type = "title" minOccurs = "1" maxOccurs = "1" />
"   </ElementType>
"   <ElementType name = "books" content = "eltOnly" model = "closed">
"      <element type = "book" minOccurs = "0" maxOccurs = "*" />
"   </ElementType>
"</Schema>


Update and insert XML Element with DataSet

Imports System
Imports System.Xml
Imports System.Xml.Schema
Imports System.IO
Imports System.Collections
Imports System.Data
Public Class MainClass
    
    Shared Sub Main()
        Dim MyDS As New DataSet()
        MyDS.ReadXmlSchema("book.xdr")
        MyDS.ReadXml("book.xml")
        MyDS.AcceptChanges()
        Dim NewBook As DataRow = MyDS.Tables("Book").NewRow()
        NewBook("Title") = "This ADO.NET Book"
        MyDS.Tables("Book").Rows.Add(NewBook)
        MyDS.WriteXml("Books_Changes.xml", XmlWriteMode.DiffGram)
        MyDS.AcceptChanges()
        MyDS.WriteXml("Books_New.xml", XmlWriteMode.IgnoreSchema)
    End Sub
End Class
"book.xdr
"<?xml version = "1.0"?>
"<Schema xmlns = "urn:schemas-microsoft-com:xml-data">
"   <ElementType name = "title" content = "textOnly" 
"      model = "closed" />
"   <ElementType name = "book" content = "eltOnly" model = "closed">
"      <element type = "title" minOccurs = "1" maxOccurs = "1" />
"   </ElementType>
"   <ElementType name = "books" content = "eltOnly" model = "closed">
"      <element type = "book" minOccurs = "0" maxOccurs = "*" />
"   </ElementType>
"</Schema>
Источник — «http://vbex.ru/index.php?title=VB.Net/XML/XML_DataSet&oldid=307»